She'd have been 29 (commissioned in 2372, PIC S3 takes place in 2401). For comparison's sake the original 1701 achieved this milestone some time between The Motion Picture and The Wrath of Khan, and as a real-world example the USS Enterprise CVN-65 was on active service with the US Navy for almost 51 years.
As I wrote earlier, The Enterprise-E was undeniably an very early Sovereign, because Sovereigns were the advanced ship in the fleet in 2373. And given with how many Soverigns we've seen in Lower Decks and Picard, the class was highly successful. They built a lot of them. It's very likely any or many of those was built before 2371.
Which means a relatively short lifetime of the Enterprise E, ending by 2386, is perfectly explicable.It could have been something as simple as it was a early Sovereign that got a big upgrade post-Insurrection, and then again post-Nemesis, but was internally dated compared to later-build Soverigns, and by 2386, the newer "Flight II" Sovereigns diverged so much from the "Flight Is" that it made more sense to retire the original ones and use them for spares, rather than keep upgrading them and crewing them. The Air Force has done this with fighters and the Navy with ships many times. The 22 "Flight II" Ticonderoga-class cruiser, for example will see their ships retire with serivce lives of 28-33 years, by the end of the decade. However the 5 "Flight Is" were all retired in the mid 2000s because they were so different from the Flight IIs internally, it didn't make sense to keep them around.
People always trout out the whole "post scarcity" argument about ship construction, but we know from visual evidence that it still takes significant manhours to build and maintain them, and even an organization as vast a Starfleet does have a finite number of personnel, and it may have been a wiser allocation of sentient-resources to to put them on a new Sovereign or split the 855 up into two smaller crewers, than it was to repair/upgrade a Flight I Sovereign that had been sustained major damage once already, in 2379.
Frankly if you consider the post-Nemesis damage the ship too, it is probably only because they are a few years out of the Dominion War and still rebuilding from losses, they even bothered to repair the Enterprise E. The US Navy, for example, repairs attack subs that periodically smash into undersea mountains, wrecking their bows, despite the enormous cost, because it needs every submarine it can get. But if that happens to one of the older ship in coming years with the planned expansion leading to new ships, it's more likely they'll just retire it and use it for parts to support the ships of that class still in service. The Enterprise E, under that logic, could very well not exist anymore because no matter what Worf did to it, it eventually got raided for spares.
All of this is head canon and theorizing of course, using real world examples, but it's all perfectly reasonable. Same with the short lifetime of the Enterprise-F, if the ships of the 2400 era utilize an entirely different technological foundation and parts configuration (former, unknown, latter is visually true... the Enterprise-F is clearly unique externally). It may make more sense for Starfleet to spread the 1600 man crew of the Enterprise-F to three newer ships of a modular design that have 500 person crews and can be supported easier, than it was to repair/upgrade a limited run design that is very resource and manpower intensive.
